萬法唯心 – Impermanence

Archive for the 'EEE' category

Digital ASIC

January 17, 2007 11:20 pm

This is what I have been busy with the whole of last week, making a Biquad filter chip at transistor level. It is a coursework in groups of four, however are group has only three people so more work! Not many Imperial undergraduate are taking the courses in final year anymore, less than 10 of us (~20%) I think in the whole course. Luckly our group work together happily and got the chip. Not the best chip in the world but we tried our best. Designing circuit at transistor level is a lot harder than VHDL and very time consuming. I was in charge of building a 32×8 ROM and here it is…

NAND - 3D view Inverter - Electric Workspace D Flip-Flop

If you are interested, click on the image to see the rest of the components that we designed. :)Sorry, I have to take out the full size images to avoid students from plagiarism.

Digital IC Design

November 4, 2006 1:26 pm

Currently doing a Digital IC Design course, at the moment we are learning to use Electric to design the layout of a circuit. It takes some time to get use to the program and now enjoying the course :). Here is a screen shot:

Inverter Layout Design 

Work Update…

September 11, 2006 10:25 pm

Have been very busy with a lot of things, including the intership… I spent the whole of last week just trying to write the Handel-C driver for reading and writing to the Flash RAM and the SRAM on the DE2 board. And also displaying using that to display a image to the screen using only 800×600 resolution. Didn't throught it will be that hard, but a lot of small things just wouldn't work and having to go a very long way to find out how to do it, which I guess happen all the time in projects. lol Here are some photos of the VGA output when I was trying to output a 8bit greyscale photo to the screen.

DE2 VGA output DE2 VGA output DE2 VGA output

So… not that easy… and after the whole week I did manage to get the photo display correctly! But it's only a greyscale image, the problem is all the RAMs on the board are only up to 16 bits wide and loading the image on to the RAM was also a challenge. Three more weeks to go, and my aim is to be able to display a colour image, video scream a camera input and write up a manual. Hopefully will get a colour image to display by the end of tomorrow :D.

Altera DE2 & Handel-C link error

August 11, 2006 11:49 am

Spent the whole of yesterday to try and fix one error. What I am doing is using to build a Handel-C project (in Celoxica DK) to create a .edf output file for the Quartus. Then using Quartus to load this design on to the DE2 board. Interface with the VHDL module works fine, but when I try to assign a input say x=0b1010 to the VHDL module, for some reason the Quartus would not recognise this input. Search everywhere I can on the internet and couldn't find a solution. At the end of the day with some luck find out how to fix it. Here is why just in case you are having the same problem as me.

In DK, the .edf file created uses VCC as the default power. However Altera Quartus expect VDD instead, hence giving the following warning when the project is being compiled.

Warning: Net "VCC" has no sources.  Ignoring net during synthesis.

Solution: Go to  Assignments>Design Entry/Synthesis, change tool name to custom and add the library mapping file installed in DK/Lmf/celoxica.lmf

Vincent 

Altera DE2 Resources

August 9, 2006 4:52 pm

Well, still working on the DE2 board. Have been making some progress since last week. At the moment, got a few VHDL modules working and started to program the board in Handel-C. Started off with simple program on Handel-C just to turn on some LEDs with the switch, now trying to port a VHDL LCD module in Handel-C. Got it to display something, well all zeros…

If you happen to be working on the DE2 board as well, you might also be looking for more examples in VHDL and Verilog. Here are some sites which I find very useful, hope you find them useful too:

Start Working!!!

July 4, 2006 1:09 pm

Started working yestereday on a research project about Handel C and a FPGA board (Altera DE2). I started off working in a very nice lab with very cold air conditioning, but I don't have access to install software on those computers. So at the end I move to a hotter room with windows, which is good becuase the other room is just too cold and no one is using it!

The aim is to get handel C to work on this board and hope to do some video processing at the end. The development board is quite cool, it even supports VGA DAC, USB, TV Decoder… The first day was just getting use to the board and run through a few tutorials, get it to display a tiger on a monitor 😀 and a lot of flashing LEDs. And today I'm suppose to start working on Handel C and find out how it works and do some excerises on it. Now taking my lunch break!! Have a look at the photos, quite interesting, more updates soon.

 DE2 flashing LEDsThis is when the board is running a demo program with flashing LEDs and outputing ALTERA DE2 on the monitor.